Kirsty Williams, Leader of the Welsh Liberal Democrats, said: “If Labour’s claims that e-cigarettes were a gateway to tobacco were correct, we should be seeing people who have never smoked a cigarette before using e-cigs now.

“In fact, the opposite is true: Labour’s survey couldn’t find a single e-cigarette user who’s never smoked a cigarette before.

“Welsh Labour Ministers must be pretty embarrassed that their own report is undermining their own argument for a vaping ban.

“It’s about time they listened to the evidence, and the thousands of people who have supported the Welsh Lib Dems’ campaign against their proposed ban, and scrapped these illiberal and illogical proposals.”

'Proposals based on evidence across the world'

A Welsh Government spokesman said: “Our proposals are based on evidence from across the world, including peer-reviewed academic research.

“The BMA, public health professionals and others support our proposals, while the World Health Organisation and other international bodies have called for greater regulation of e-cigarettes. 40 other countries have already taken similar steps.

“Let’s be absolutely clear, our Bill does not propose to ban e-cigarettes, nor does it intend to prevent their use for smoking cessation.